Lubricating composition

ABSTRACT

The present application is directed to additive package compositions and lubricant compositions comprising a hydrocarbyl substituted triazole compound. Methods of using the compositions to lubricate a machine and provide lead corrosion protection are also disclosed.

DESCRIPTION OF THE DISCLOSURE

1. Field of the Disclosure

The present disclosure is directed to additive and lubricant compositions and methods for use thereof. More particularly, this invention is directed to an additive composition comprising a triazole compound.

2. Background of the Disclosure

Lead and lead alloys are known for use in many types of engines and other machines. For example, lead alloys are known for use in bearings used in many applications, including main bearings used in spark ignition and compression-ignition internal combustion engines, also referred to as diesel engines.

Lubricants employed in lead containing engines have been observed to cause undesirable lead corrosion. While lead corrosion inhibitors are known for reducing lead corrosion caused by these lubricant formulations, lead corrosion can still be problematic. Accordingly, novel lead corrosion inhibitors are desirable in the art for providing improved lead corrosion protection.

Metal corrosion in general can be a particular problem in diesel engines. Among the various types of diesel engines are the medium speed diesel engines, which are used in applications where thousands of horsepower (e.g., 2000 to 10,000 horsepower) are needed. Typically, these engines run at a speed of about 100 to 1,200 rpm. This demanding environment results in oxidation of the oil, which can result in corrosion of the metals present in the engine.

Some medium speed diesel engines also have silver parts, such as silver bearings. Thus, apart from providing stability against oxidation and protection against the formation of sludge and carbonaceous deposits, lubricating compositions intended for use in medium speed diesel engines are often formulated with specialized silver protecting agents in order that silver bearings in the engine are not attacked either by the additives in the oil or by the decomposition products produced during extended engine operation. Such agents, often referred to as silver lubricity agents, protect against extreme pressure, wear and corrosion.

A typical engine lubricating composition might comprise, for example, detergents, dispersants, antioxidants, foam inhibitors, rust inhibitors, extreme pressure agents and antiwear agents. The most commonly used extreme pressure and antiwear agents are sulfur-containing agents, such as zinc dialkyldithiophosphates (ZDDP). However, it is well known that some sulfur-containing agents cannot be used in engines having silver parts given their known propensity to damage the silver bearings. This recognized tendency is explained, for example, in U.S. Pat. No. 4,428,850. Thus, it is desirable to find lubricant compositions that can provide oxidation protection and in some cases can be essentially free of these potentially damaging sulfur-containing extreme pressure or antiwear agents, such as ZDDP, while at the same time providing protection against corrosion of metals, such as lead.

SUMMARY OF THE DISCLOSURE

In accordance with the disclosure, one aspect of the present application is directed to an additive package composition. The additive package composition comprises a diluent and a hydrocarbyl substituted triazole compound, with the proviso that the triazole compound is not an alkyl bis-3-amino-1,2,4-triazole or an oleyl-1,2,4-triazole-3-amine, and with the further proviso that the composition is substantially free of compounds containing phosphorus.

Another aspect of the present application is directed to a lubricant composition. The lubricant composition comprises a major amount of a base oil and a minor amount of a hydrocarbyl substituted triazole compound, with the proviso that the triazole compound is not an alkyl bis-3-amino-1,2,4-triazole or an oleyl-1,2,4-triazole-3-amine, and with the further proviso that the composition is substantially free of compounds containing phosphorus.

Another aspect of the present application is directed to a method of improving lead corrosion protection of a lubricant composition. The method comprises providing to a machine a lubricant composition comprising a major amount of a base oil and a minor amount of a triazole compound, with the proviso that the triazole compound is not an alkyl bis-3-amino-1 2,4-triazole or an oleyl-1,2,4-triazole-3-amine, and with the further proviso that the composition is substantially free of compounds containing phosphorus. The lubricant composition provides improved lead corrosion protection as compared to the same composition that is devoid of the triazole compound, where both compositions are employed under the same machine operating conditions over the same period of time.

Another aspect of the present application is directed to a method for operating a machine. The method comprises providing to a machine a lubricant composition comprising a major amount of a base oil and a minor amount of a triazole compound, with the proviso that the triazole compound is not an alkyl bis-3-amino-1,2,4-triazole or an oleyl-1,2,4-triazole-3-amine, and with the further proviso that the composition is substantially free of compounds containing phosphorus.

Another aspect of the present application is directed to a method of lubricating at least one moving part of a machine. The method comprises contacting the at least one moving part with a lubricant composition comprising a major amount of a base oil and a minor amount of a triazole compound, with the proviso that the triazole compound is not an alkyl bis-3-amino-1,2,4-triazole or an oleyl-1,2,4-triazole-3-amine, and with the further proviso that the composition is substantially free of compounds containing phosphorus.

Additional embodiments and advantages of the disclosure will be set forth in part in the description which follows, and/or can be learned by practice of the disclosure. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure, as claimed.

DESCRIPTION OF THE EMBODIMENTS

The present disclosure generally relates to a lubricant composition comprising a major amount of a base oil and a minor amount of a hydrocarbyl substituted triazole compound, with the proviso that the triazole compound is not alkyl bis-3-amino-1,2,4-triazole or an oleyl-1,2,4-triazole-3-amine. In some embodiments, the composition is also substantially free of compounds containing phosphorus, as will be discussed in greater detail below. The triazole compounds of the present application can offer one or more of the following benefits to lubricant compositions, including: increased oxidation protection, decreased lead corrosion, decreased silver corrosion and decreased copper corrosion.

As used herein, the term “major amount” is understood to mean an amount greater than or equal to 50 wt. %, for example from about 80 to about 98 wt. % relative to the total weight of the composition. Moreover, as used herein, the term “minor amount” is understood to mean an amount less than 50 wt. % relative to the total weight of the composition.

A triazole compound suitable for use in the compositions of the present disclosure can be any hydrocarbyl substituted triazole compound, with the exception of an alkyl bis-3-amino-1,2,4-triazole and an oleyl-1,2,4-triazole-3-amine. In some embodiments the triazole compound is a 1,2,3-triazole compound. In other embodiments the triazole compound is a 1,2,4-triazole compound.

Suitable non-limiting examples of the 1,2,4-triazole compound include compounds of formula I:

where R¹, R² and R³ are independently chosen from hydrogen and hydrocarbyl groups. Examples of suitable hydrocarbyl groups include linear, branched or cyclic groups chosen from alkyl groups, alkyl amine groups, alkenyl groups, alkenyl amine groups, and aryl groups. In one embodiment of Formula I, R¹ is a linear or branched hydrocarbyl group and R² and R³ are hydrogen.

For example, in one embodiment, the triazole can be a compound of formula II,

where R′ and R″ are independently chosen from hydrogen and hydrocarbyl groups, with the proviso that at least one of R′ and R″ is not hydrogen. Examples of suitable hydrocarbyl groups include C₂ to C₅₀ linear, branched or cyclic alkyl groups; C₂ to C₅₀ linear, branched or cyclic alkenyl groups; and substituted or unsubstituted aryl groups, such as phenyl groups, tolyl groups and xylyl groups.

An example of a triazole compound suitable for use herein is a triazole of the compound of formula II, wherein both R′ and R″ are chosen from linear or branched C₄to C₁₂ alkyl groups, such as isobutyl groups, 2-ethyl hexyl groups, 2-ethyl heptyl groups, and 3 propyl heptyl groups. One such suitable compound can be commercially obtained from Ciba under the tradename Irgamet® 30.

As used herein, the term “hydrocarbyl group” or “hydrocarbyl” is used in its ordinary sense, which is well-known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly attached to the remainder of a molecule and having a predominantly hydrocarbon character. Examples of hydrocarbyl groups include:

-   -   (1) hydrocarbon substituents, that is, aliphatic (e.g., alkyl or         alkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl)         substituents, and aromatic-, aliphatic-, and         alicyclic-substituted aromatic substituents, as well as cyclic         substituents wherein the ring is completed through another         portion of the molecule (e.g., two substituents together form an         alicyclic radical);     -   (2) substituted hydrocarbon substituents, that is, substituents         containing non-hydrocarbon groups which, in the context of the         description herein, do not alter the predominantly hydrocarbon         substituent (e.g., halo (especially chloro and fluoro), hydroxy,         alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulfoxy);     -   (3) hetero-substituents, that is, substituents which, while         having a predominantly hydrocarbon character, in the context of         this description, contain other than carbon in a ring or chain         otherwise composed of carbon atoms. Hetero-atoms include sulfur,         oxygen, nitrogen, and encompass substituents such as pyridyl,         furyl, thienyl, and imidazolyl. In general, no more than two, or         as a further example, no more than one, non-hydrocarbon         substituent will be present for every ten carbon atoms in the         hydrocarbyl group; in some embodiments, there will be no         non-hydrocarbon substituent in the hydrocarbyl group.

The hydrocarbyl substituted triazole compound can be present in the lubricant compositions in any effective amount, which can be readily determined by one of ordinary skill in the art. In an embodiment, lubricating compositions of the present application can comprise from about 0.005 wt. % to about 0.5 wt. %, or greater, and for example from about 0.01 wt. % to about 0.1 wt. %, of the triazole compound, relative to the total weight of the lubricating composition. In another embodiment, the lubricant composition of the present disclosure can comprise from about 0.02 wt. % to about 0.05 wt. % of the triazole compound, relative to the total weight of the lubricant composition.

The lubricant compositions disclosed herein, including the additive compositions that are discussed in more detail below, can optionally contain additives, such as dispersants, ash-containing detergents, ashless-detergents, pour point depressing agents, viscosity index improving agents, friction modifying agents, extreme pressure agents, rust inhibitors, supplemental antioxidants, supplemental corrosion inhibitors, anti-foam agents, and combinations thereof.

In some embodiments, such as where the lubricant compositions do not contain ZDDP antiwear agents, the optional additives can include supplemental corrosion inhibitors. Non-limiting examples of such corrosion inhibitors include silver protectants, such as the aminoguanidine monooleamide compounds taught, for example, in U.S. Pat. No. 4,948,523, the disclosure of which is hereby incorporated by reference in its entirety. Another example of supplemental corrosion inhibitors/dispersants that can be included in the compositions of the present application could include a second triazole compound that is different from the triazole compounds of the present application. One example of a suitable second triazole compound is the bis-3-amino-1,2,4-triazole compounds taught, for example, in U.S. Pat. Nos. 5,174,915, and 4,871,465, both of which disclosures are hereby incorporated by reference in their entirety. Other examples of possible additional triazoles include the oleyl-1,2,4-triazole-3-amines discussed in U.S. Pat. No. 4,948,523, the disclosure of which is incorporated herein by reference, as described above. Yet other examples of suitable triazoles include those disclosed in copending applications [Attorney Docket Nos. 0013.0111, 0013.0084, and 0013.0090], the disclosures of which are hereby incorporated by reference in their entirety. Such supplemental corrosion inhibitors may be useful, for example, in machines containing silver parts and in medium speed diesel engines (whether or not they contain silver parts).

In an embodiment, the lubricant compositions of the present application can be essentially free, such as devoid, of compounds containing free active sulfur. As used herein, the phrase “active sulfur” is defined as sulfur containing compounds which would substantially react with machine parts to form metal sulfides at normal engine running temperatures ranging from about 100° C. to below about 400° C. Active sulfur is distinguished from non-active sulfur, which does not substantially react at temperatures under 400° C., but which may sufficiently react to form metal sulfides at temperatures above 400° C. so as to protect engine parts under extreme pressure conditions, or where boundary conditions exist. One of ordinary skill in the art would readily understand that temperatures significantly above 400° can occur at various positions in engines that typically operate at lower temperatures, such as below 400° C., due to these boundary regions and extreme pressure regions. Such boundary regions and extreme pressure regions can occur, for example, when a particular engine part, such as a bearing, is placed under load. Non-active sulfur compounds can be employed that will react to protect engine parts as these higher temperatures, while not substantially reacting at the generally lower engine operating temperatures. Accordingly, one of ordinary skill in the art understands that compounds containing active sulfur, such as zinc dialkyldithiophosphate (ZDDP), can exert a measurable deleterious effect upon some machines, such as medium speed diesel engines or machines that contain silver parts, while non-active sulfur compounds can still be employed to protect engine parts in these machines. For at least this reason, it may be desirable to omit active sulfur compounds from formulations intended for use in such machines. One skilled in the art would know how to determine the effect of sulfur containing compounds on machine parts, such as, for example, by measuring the amount of silver dissolved in the lubricant and/or the amount of deposits on the silver parts. The term “essentially free” is defined for purposes of this application to be concentrations having substantially no measurable deleterious effect.

In some embodiments, the lubricant compositions of the present application are substantially free, such as devoid, of compounds containing phosphorus. In other embodiments, the compositions of the present application can be substantially free of compounds containing boron. It can be desirable to omit phosphorus and/or boron containing compounds from formulations of the present application so that these elements can be used as markers to indicate lubricant contamination. For example, railroad engine oils are generally formulated to be free of phosphorus and boron. While in use, the oils are periodically checked for phosphorus and/or boron, the presence of which can indicate that the oil has been contaminated with e.g., ZDDP or, in the case of boron, boron containing coolants, during engine operation. In this manner, the phosphorus and/or boron act as markers to indicate contamination of the lubricant. By the phrase substantially free is meant that the composition comprises only trace amounts of phosphorus and/or boron, so that concentrations of these elements will have substantially no effect on the ability of phosphorus and boron to be used as markers.

Base oils suitable for use in formulating the disclosed compositions can be selected from any of the synthetic or mineral oils or mixtures thereof. Mineral oils include animal oils and vegetable oils (e.g., castor oil, lard oil) as well as other mineral lubricating oils such as liquid petroleum oils and solvent treated or acid-treated mineral lubricating oils of the paraffinic, naphthenic or mixed paraffinic-naphthenic types. Oils derived from coal or shale are also suitable. Further, oils derived from a gas-to-liquid process are also suitable.

The base oil can be present in a major amount, wherein “major amount” is understood to mean greater than or equal to 50%, for example from about 80 to about 98 percent by weight of the lubricant composition.

The base oil can have any desired viscosity that is suitable for the intended purpose. Examples of suitable engine oil kinematic viscosities can range from about 2 to about 150 cSt and, as a further example, from about 5 to about 15 cSt at 100° C. Thus, for example, base oils can be rated to have viscosity ranges of about SAE 15 to about SAE 250, and as a further example, from about SAE 20W to about SAE 50. Suitable automotive oils also include multi-grade oils such as 15W-40, 20W-50, 75W-140, 80W-90, 85W-140, 85W-90, and the like.

Non-limiting examples of synthetic oils include hydrocarbon oils such as polymerized and interpolymerized olefins (e.g., polybutylenes, polypropylenes, propylene isobutylene copolymers, etc.); polyalphaolefins such as poly(1-hexenes), poly-(1-octenes), poly(1-decenes), etc. and mixtures thereof; alkylbenzenes (e.g., dodecylbenzenes, tetradecylbenzenes, di-nonylbenzenes, di-(2-ethylhexyl)benzenes, etc.); polyphenyls (e.g., biphenyls, terphenyl, alkylated polyphenyls, etc.); alkylated diphenyl ethers and alkylated diphenyl sulfides and the derivatives, analogs and homologs thereof and the like.

Alkylene oxide polymers and interpolymers and derivatives thereof where the terminal hydroxyl groups have been modified by esterification, etherification, etc., constitute another class of known synthetic oils that can be used. Such oils are exemplified by the oils prepared through polymerization of ethylene oxide or propylene oxide, the alkyl and aryl ethers of these polyoxyalkylene polymers (e.g., methyl-polyisopropylene glycol ether having an average molecular weight of about 1000, diphenyl ether of polyethylene glycol having a molecular weight of about 500-1000, diethyl ether of polypropylene glycol having a molecular weight of about 1000-1500, etc.) or mono- and polycarboxylic esters thereof, for example, the acetic acid esters, mixed C₃₋₈ fatty acid esters, or the C₁₃ Oxo acid diester of tetraethylene glycol.

Another class of synthetic oils that can be used includes the esters of dicarboxylic acids (e.g., phthalic acid, succinic acid, alkyl succinic acids, alkenyl succinic acids, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, malonic acid, alkyl malonic acids, alkenyl malonic acids, etc.) with a variety of alcohols (e.g., butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycol monoether, propylene glycol, etc.) Specific examples of these esters include dibutyl adipate, di(2-ethylhexyl)sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dieicosyl sebacate, the 2-ethylhexyl diester of linoleic acid dimer, the complex ester formed by reacting one mole of sebacic acid with two moles of tetraethylene glycol and two moles of 2-ethylhexanoic acid and the like.

Esters useful as synthetic oils also include those made from C₅₋₁₂ monocarboxylic acids and polyols and polyol ethers such as neopentyl glycol, trimethylol propane, pentaerythritol, dipentaerythritol, tripentaerythritol, etc.

Hence, the base oil used which can be used to make the compositions as described herein can be selected from any of the base oils in Groups I-V as specified in the American Petroleum Institute (API) Base Oil Interchangeability Guidelines. Such base oil groups are as follows:

Group I contain less than 90% saturates and/or greater than 0.03% sulfur and have a viscosity index greater than or equal to 80 and less than 120; Group II contain greater than or equal to 90% saturates and less than or equal to 0.03% sulfur and have a viscosity index greater than or equal to 80 and less than 120; Group III contain greater than or equal to 90% saturates and less than or equal to 0.03% sulfur and have a viscosity index greater than or equal to 120; Group IV are polyalphaolefins (PAO); and Group V include all other basestocks not included in Group I, II, III or IV.

The test methods used in defining the above groups are ASTM D2007 for saturates; ASTM D2270 for viscosity index; and one of ASTM D2622, 4294, 4927 and 3120 for sulfur.

Group IV basestocks, i.e. polyalphaolefins (PAO) include hydrogenated oligomers of an alpha-olefin, the most important methods of oligomerisation being free radical processes, Ziegler catalysis, and cationic, Friedel-Crafts catalysis.

The polyalphaolefins typically have viscosities in the range of 2 to 100 cSt at 100° C., for example 4 to 8 cSt at 100° C. They can, for example, be oligomers of branched or straight chain alpha-olefins having from about 2 to about 30 carbon atoms, non-limiting examples include polypropenes, polyisobutenes, poly-1-butenes, poly-1-hexenes, poly-1-octenes and poly-1-decene. Included are homopolymers, interpolymers and mixtures.

Regarding the balance of the basestock referred to above, a “Group I basestock” also includes a Group I basestock with which basestock(s) from one or more other groups can be admixed, provided that the resulting admixture has characteristics failing within those specified above for Group I basestocks.

Exemplary basestocks include Group I basestocks and mixtures of Group II basestocks with Group I bright stock.

Basestocks suitable for use herein can be made using a variety of different processes including but not limited to distillation, solvent refining, hydrogen processing, oligomerisation, esterification, and re-refining.

The base oil can be an oil derived from Fischer-Tropsch synthesized hydrocarbons. Fischer-Tropsch synthesized hydrocarbons can be made from synthesis gas containing H₂ and CO using a Fischer-Tropsch catalyst. Such hydrocarbons typically require further processing in order to be useful as the base oil. For example, the hydrocarbons can be hydroisomerized using processes disclosed in U.S. Pat. Nos. 6,103,099 or 6,180,575; hydrocracked and hydroisomerized using processes disclosed in U.S. Pat. Nos. 4,943,672 or 6,096,940; dewaxed using processes disclosed in U.S. Pat. No. 5,882,505; or hydroisomerized and dewaxed using processes disclosed in U.S. Pat. Nos. 6,013,171; 6,080,301; or 6,165,949.

Unrefined, refined and rerefined oils, either mineral or synthetic (as well as mixtures of two or more of any of these) of the type disclosed hereinabove can be used in the base oils. Unrefined oils are those obtained directly from a mineral or synthetic source without further purification treatment. For example, a shale oil obtained directly from retorting operations, a petroleum oil obtained directly from primary distillation or ester oil obtained directly from an esterification process and used without further treatment would be an unrefined oil. Refined oils are similar to the unrefined oils except they have been further treated in one or more purification steps to improve one or more properties. Many such purification techniques are known to those skilled in the art such as solvent extraction, secondary distillation, acid or base extraction, filtration, percolation, etc. Rerefined oils are obtained by processes similar to those used to obtain refined oils applied to refined oils which have been already used in service. Such rerefined oils are also known as reclaimed or reprocessed oils and often are additionally processed by techniques directed to removal of spent additives, contaminants, and oil breakdown products.

In some embodiments, the compounds of the present application can be added to a lubricant composition in the form of a lubricant additive package composition. These are concentrates dissolved in a diluent, such as mineral oil, synthetic hydrocarbon oils, and mixtures thereof. When added to the base oil, the additive package composition can provide an effective concentration of the additives in the base oil. The amount of the hydrocarbyl substituted triazole compounds of the present application in the additive package can vary from about 0.05 wt % to about 5 wt %, or greater, of the additive package, such as from about 0.1 wt % to about 0.5 wt %.

The additive compositions can be formulated to include any of the optional additives discussed in the present application. In embodiments where the additive composition is formulated for medium speed diesel engines, the optional additives discussed herein for medium speed diesel engines can also be employed.

According to various aspects of the present application, there is a method of improving lead corrosion protection in a lubricant composition. As used herein, the term “improving lead corrosion protection” is understood to mean enhancing the lead corrosion protection that a composition can provide to a machine, as compared to the same composition that is devoid of the triazole compound of the present application, where both compositions are employed under the same machine operating conditions over the same period of time. The method of improving lead corrosion protection can comprise providing to a machine a lubricant composition comprising a major amount of a base oil; and a minor amount of a triazole compound of the present application. In one embodiment, the machine is a diesel engine, such as a medium speed diesel engine.

According to various aspects, there is also disclosed a method of lubricating at least one moving part of a machine, said method comprising contacting at least one moving part with a lubricant composition comprising a major amount of a base oil and a minor amount of the disclosed triazole compound of the present application.

In other embodiments, there is also disclosed a method for operating a machine comprising adding a lubricant composition comprising a major amount of a base oil and a minor amount of the disclosed triazole compound of the present application.

The machine in the disclosed methods can be selected from the group consisting of spark ignition and compression-ignition internal combustion engines, including diesel engines, marine engines, rotary engines, turbine engines, locomotive engines, propulsion engines, aviation piston engines, stationary power generation engines, continuous power generation engines, engines comprising silver parts, and engines comprising lead parts. Moreover, the at least one moving part can comprise a gear, piston, bearing, rod, spring, camshaft, crankshaft, and the like

The lubricant composition can be any composition that would be effective in lubricating a machine. In an aspect, the composition is selected from the group consisting of medium speed diesel engine oils, passenger car motor oils and heavy duty diesel engine oils. In an embodiment, the composition is a medium speed diesel engine oil.

EXAMPLES

The following examples are illustrative of the invention and its advantageous properties. In these examples as well as elsewhere in this application, all parts and percentages are by weight unless otherwise indicated. It is intended that these examples are being presented for the purpose of illustration only and are not intended to limit the scope of the invention disclosed herein.

Lubricant compositions that were substantially free of phosphorus and boron, as well as essentially free of zinc dialkyl dithiophosphate (ZDDP) and other compounds containing active sulfur, were tested for their ability to protect against lead and copper uptake, viscosity increase and oxidation. All example lubricant compositions below include a base oil that was identified as being a “severe” mineral oil base stock for lead pickup.

Example 1

Example 1 included 0.20 wt. % of a 1,2,4-triazole compound (Irgamet® 30, from Ciba),; a commercial, ZDDP free Additive Package 1 containing an aminoguanidine monooleamide (AGMO) having an unsaturated alkyl group; and base oil.

Example 2

Example 2 included 0.20 wt. % of the 1,2,4-triazole compound of Example 1; Additive Package 1 containing an AGMO compound of similar to that of Example I, except that is had a saturated alkyl group; and base oil.

Example 3

Example 1 included 0.20 wt. % of the 1,2,4-triazole compound of Example I; Additive Package 1 without an AGMO compound; and base oil.

Comparison Example 1A

The formulation of Example 1 without a 1,2,4-triazole compound.

Comparison Example 2A

The formulation of Example 2 without a 1,2,4-triazole compound.

Comparison Example 3A

The formulation of Example 3 without a 1,2,4-triazole compound.

Comparison Example 4A

Comparison Example 4 included a commercially available, ZDDP free Additive Package 2 that is different from Additive Package 1, and base oil.

The seven lubricant compositions were subjected an Ethyl Oxidation Test. Oxygen was bubbled through a test tube containing iron, copper and lead coupons suspended in one of the lubricant compositions of Examples 1 to 3 or Comparative Examples 1 to 4. An air condenser retained most of the volatiles, and the lubricant composition was sampled and analyzed every 24 hours. The used lubricant compositions were evaluated for oxidation control by methods well known in the art for measuring kinematic viscosity increase; infrared carbonyl absorptions of the oil oxidation products; oil lead content; and oil copper content.

Regarding the viscosity increase data, the greater the increase in viscosity, the less stable a particular lubricant composition is to oxidation. The results are provided in Tables 1 and 2 below. Regarding the Fourier Transform Infrared Spectroscopy (FTIR) carbonyl absorption data, the greater the carbonyl absorption, the less oxidation protection that particular lubricant composition imparts to the machine.

TABLE 1 Viscosity Increase Percent Increase of Kinematic Viscosity at 100° C. Example Nos. Test Time 1 1A 2 2A 3 3A 4A  0 Hrs 0 0 0 0 0 0 0 24 Hrs 2.76 2.79 2.83 3.56 1.73 4.41 −1.24 48 Hrs 4.18 5.19 4.38 5.97 3.59 18.1 0.83 72 Hrs 6.74 6.99 6.27 8.59 6.18 48.45 3.09 80 Hrs 6.54 7.92 6.47 9.46 6.91 43.38 3.3 96 Hrs 7.35 9.45 7.75 11.48 8.98 63.33 5.85 120 Hrs  8.96 11.98 10.31 14.5 12.5 106.19 11.69

TABLE 2 Carbonyl Content Increase FTIR Carbonyl Absorption abs/cm @ 1710 cm⁻¹ Example Nos. Test Time 1 1A 2 2A 3 3A 4A  0 Hrs 0 0 0 0 0 0 0 24 Hrs 6.99 9.93 6.90 11.23 7.93 21.42 5.72 48 Hrs 8.69 13.44 9.83 16.54 12.68 61.10 10.88 72 Hrs 10.84 17.34 12.56 22.05 18.08 118.04 17.11 80 Hrs 11.63 18.44 13.34 21.31 19.41 130.86 19.09 96 Hrs 13.11 21.25 15.78 26.57 24.45 164.27 25.66 120 Hrs  15.97 24.67 18.90 30.76 30.27 191.36 37.87

As shown in Table 1, the example compositions 1, 2 and 3 each illustrate a lower viscosity increase compared with Comparative Examples 1A, 2A and 3A, indicating that the 1,2,4-triazole compound of the example compositions improved the oxidation stability of the lubricant compositions. In addition, example compositions 1 and 2 had a lower viscosity increase, and example 3 had a comparable viscosity increase, when compared with Comparative Example 4, also indicating good oxidation stability performance by the 1,2,4-triazole compound formulations.

As shown in Table 2, the example compositions 1, 2 and 3 each illustrated a lower carbonyl absorption compared with Comparative Examples 1A, 2A and 3A, indicating that the 1,2,4-triazole compound of the example compositions increased the oxidation protection of the lubricant compositions. In addition, example compositions 1 and 2 had a lower carbonyl absorption, and example 3 had a comparable carbonyl absorption, when compared with Comparative Example 4, also indicating good oxidation protection performance by the triazole compound formulations.

Tables 3 and 4 show test data for lead and copper content of the example formulations above. As shown in Table 3 and 4, the example compositions 1, 2 and 3 each illustrated a substantially lower lead and copper content compared with Comparative Examples 1A, 2A and 3A, indicating that the 1,2,4-triazole compound of the example compositions acted as an effective lead and copper corrosion inhibitor in the lubricant compositions. In addition, example compositions 1 and 2 had a substantially lower lead and copper content when compared with Comparative Example 4A, also indicating good lead and copper corrosion protection by the 1,2,4-triazole compound formulations of the present application.

TABLE 3 Oil Lead Content Increase Oil Lead Content (PPM) Example Nos. Test Time 1 1A 2 2A 3 3A 4A  0 Hrs 0 0 0 0 0 0 0 24 Hrs 14 35 4 19 2 52 31 48 Hrs 19 79 13 110 27 1519 40 72 Hrs 37 288 46 534 262 3466 158 80 Hrs 51 435 71 783 454 4109 297 96 Hrs 115 878 194 1539 1155 5622 909 120 Hrs  332 1886 554 3111 2963 7749 2868

TABLE 4 Oil Copper Content Increase Oil Copper Content (PPM) Example Nos. Test Time 1 1A 2 2A 3 3A 4A  0 Hrs 0 0 0 0 0 0 0 24 Hrs 1 5 1 4 1 12 4 48 Hrs 1 6 1 6 1 33 5 72 Hrs 2 8 2 8 2 49 7 80 Hrs 2 8 2 9 3 61 8 96 Hrs 3 10 3 11 5 94 12 120 Hrs  4 14 4 17 12 161 21

Table 5 shows the actual lead loss from the metallic coupons used in the above Ethyl Oxidation Test after 120 hours. This data indicates that the example compositions containing the 1,2,4-triazole compound provided excellent lead protection compared to the comparative compositions.

TABLE 5 Lead Coupon Weight Loss Lead Coupon Wieght Loss (% @ 120 HOURS) Example Nos. 1 1A 2 2A 3 3A 4 % LEAD LOST 0.90 5.12 1.58 8.39 7.95 22.63 7.69

Example 5

Example 5 included 0.025 wt. % of a 1,2,4-triazole compound (Irgamet® 30 from Ciba); a commercial, ZDDP free Additive Package 1 containing an aminoguanidine monooleamide (AGMO) having an unsaturated alkyl group; and base oil.

Comparison Example 5A

The formulation of Example 5 without a 1,2,4-triazole compound.

Comparison Example 6A.

Comparison Example 4 included a commercially available, ZDDP free Additive Package 2 that is different from Additive Package 1, and base oil.

The lubricant compositions of Examples 5, 5A and 6A were subjected to an Ethyl Oxidation Test. Oxygen was bubbled through a test tube containing one of three different sample portions of a GE medium speed diesel engine bearing. The GE bearings had a multi-layered construction with the top layer being a very thin lead/tin alloy (90% lead, 10% tin); a second layer underlying the top layer comprising a copper/tin/lead alloy (2.5 wt % copper, 10 wt % tin, 87.5 wt % lead); and a third layer underlying the second layer, the third layer having a heterogeneous composition of 25wt % lead in a bronze alloy (70+wt % copper, 2+wt % tin).

Each of the bearing layers was tested for corrosion protection with and without the triazole using the following bearing sample portions: (1) Bearing portion 1 (B1), which had only the top lead/tin alloy layer exposed; (2) Bearing portion 2 (B2), from which the top lead/tin alloy layer was removed, so that only the second copper/tin/lead alloy layer was exposed; and (3) Bearing portion 3 (B3), from which the top lead/tin alloy layer and the second copper/tin/lead alloy layers were removed, so that only the third heterogeneous layer was exposed.

Each bearing portion type B1, B2 and B3 was tested in all three lubricant compositions of Examples 5, 5A and 6A above by suspending a bearing portion of each type in a test tube containing one of the lubricant compositions of Examples 5, 5A and 6A. A lead coupon was also tested in the same composition used to test each bearing portion, the results of which are reported in Table 6 as “Associated Lead Coupons for B1, B2, B3.” An air condenser retained most of the volatiles, and the lubricant composition was sampled and analyzed every 24 hours. The used lubricant compositions were evaluated for oxidation control by methods well known in the art for measuring kinematic viscosity increase; infrared carbonyl absorptions of the oil oxidation products; oil lead content; and oil copper content. Results are shown in Tables 6 to 9 below.

TABLE 6 USED OIL LEAD CONTENT (PPM) Used Oil Lead Content For Used Oil Lead Content For Used Oil Lead Content For Example 5 Compositions Example 5A Compositions Example 6A Compositions Test Associated Lead Associated Lead Associated Lead Time Coupons for Coupons for Coupons for (hrs) B1 B2 B3 B1, B2, B3 B1 B2 B3 B1, B2, B3 B1 B2 B3 B1, B2, B3 24 1 1 1 7, 3, 10 1 1 1 18, 20, 26 1 0 3 23, 24, 28 48 2 0 0 21, 9, 18 0 4 0 54, 70, 64 0 1 2 32, 30, 34 72 2 1 1 79, 52, 41 6 8 11 285, 432, 267 3 6 12 226, 270, 92 80 2 1 3 125, 89, 57 8 11 23 430, 635, 396 6 9 24 455, 556, 179 96 5 4 11 288, 204, 116 12 14 64 813, 1261, 666 12 15 72 1278, 1593, 495 120 10 7 50 720, 602, 308 18 22 148 1633, 2463, 1450 25 24 207 4318, 6070, 176

Table 6 shows test data for used oil lead content of the example formulations 5, 5A and 6A above. As shown in Table 6, example composition 5 demonstrated a substantially lower lead content compared with Comparative Examples 5A and 6A, indicating that the 1,2,4-triazole compound of the example compositions acted as an effective lead corrosion inhibitor in the lubricant compositions at the 0.025% concentrations used.

Table 7, below, shows the actual lead loss, in milligrams, from the metallic coupons used in the above Ethyl Oxidation Test for examples 5, 5A and 6A after 120 hours. This data indicates that Example Composition 5 containing the 1,2,4-triazole compound provided excellent lead protection compared to the comparative compositions.

TABLE 7 Bearing and Coupon Lead Weight Loss Example 5 Example 5A Example 6A Associated Associated Associated Lead Lead Coupons Lead Coupons Coupons for for for B1 B2 B3 B1, B2, B3 B1 B2 B3 B1, B2, B3 B1 B2 B3 B1, B2, B3 Lead Weight 2.8 4.0 13.7 183, 369, 80 5.5 5.7 39.3 427, 647, 381 6.9 6.6 56.1 1121, 1575, 455 Loss (mgs @ 120 hrs)

As shown in Table 8, the example composition 5 demonstrated a lower viscosity increase compared with Comparative Example 5A, indicating that the 1,2,4-triazole compound of the example compositions improved the oxidation stability of the lubricant compositions. In addition, example composition 5 had a lower viscosity increase when compared with Comparative Example 6A, also indicating good oxidation stability performance by the triazole compound formulations.

TABLE 8 Viscosity Increase Example 5 Example 5A Example 6A Associated Associated Associated Lead Lead Lead Coupons for Coupons for Coupons for B1 B2 B3 B1, B2, B3 B1 B2 B3 B1, B2, B3 B1 B2 B3 B1, B2, B3 % 10.1 9.9 8.6 10.0, 9.9, 9.3 12.7 16.9 11.9 12.5, 14.7, 15.5 16.2 10.2 15.6, 20.5, 11.0 Viscosity 13.3 Increase @ 120 hours

As shown in Table 9, the example composition 5 demonstrated a lower carbonyl absorption compared with Comparative Example 5A, indicating that the 1,2,4-triazole compound of the example compositions increased the oxidation protection of the lubricant compositions. In addition, example compositions 5 had a lower carbonyl absorption when compared with Comparative Example 6A, also indicating good oxidation protection.

TABLE 9 Carbonyl Content Increase (FTIR carbonyl absorption) Example 5 Example 5A Example 6A Associated Associated Associated Lead Lead Coupons Lead Coupons Coupons for for for B1 B2 B3 B1, B2, B3 B1 B2 B3 B1, B2, B3 B1 B2 B3 B1, B2, B3 carbonyl 21 20 17 21, 19, 19 28 37 25 25, 27, 27 51 51 34 49, 58, 36 absorption Abs/cm @ 1710 cm⁻¹ @ 120 hours

It is noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the,” include plural referents unless expressly and unequivocally limited to one referent. Thus, for example, reference to “an antioxidant” includes two or more different antioxidants. As used herein, the term “include” and its grammatical variants are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that can be substituted or added to the listed items

For the purposes of this specification and appended claims, unless otherwise indicated, all numbers expressing quantities, percentages or proportions, and other numerical values used in the specification and claims, are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

While particular embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are or can be presently unforeseen can arise to applicants or others skilled in the art. Accordingly, the appended claims as filed and as they can be amended are intended to embrace all such alternatives, modifications variations, improvements, and substantial equivalents. 

1. An additive package composition comprising: a diluent; and a hydrocarbyl substituted triazole compound, with the proviso that the triazole compound is not an alkyl bis-3-amino-1,2,4-triazole or an oleyl-1,2,4-triazole-3-amine, and with the further proviso that the composition is substantially free of compounds containing phosphorus.
 2. The additive package composition of claim 1, wherein the triazole compound is present in an amount ranging from about 0.1 wt % to about 5 wt % relative to the total weight of the additive package composition.
 3. The additive package composition of claim 1, further comprising one or more additional additives chosen from dispersants, detergents, anti-wear agents, supplemental antioxidants, viscosity index improvers, pour point depressants, corrosion inhibitors, rust inhibitors, foam inhibitors, anti-swell agents and friction modifiers.
 4. The additive package composition of claim 1, wherein the triazole compound is a 1,2,4-triazole compound.
 5. The additive package composition of claim 4, wherein the 1,2,4-triazole compound is a compound of formula I:

where R¹, R² and R³ are independently chosen from a hydrogen atom and a hydrocarbyl group having at least 3 carbon atoms.
 6. The additive package composition of claim 5, wherein R¹ is a linear or branched hydrocarbyl group, and where R² and R³ are hydrogen atoms.
 7. The additive package composition of claim 1, wherein the triazole compound is a compound of the formula II,

where R′ and R″ are independently chosen from hydrogen and a C₂ to C₅₀ linear or branched alkyl group, with the proviso that at least one of R′ and R″ is not hydrogen.
 8. The additive package composition of claim 7, wherein R′ and R″ are independently chosen from C₄ to C₁₂ linear or branched alkyl groups.
 9. A lubricant composition comprising: a major amount of a base oil; and a minor amount of a hydrocarbyl substituted triazole compound, with the proviso that the triazole compound is not an alkyl bis-3-amino-1,2,4-triazole or an oleyl-1,2,4-triazole-3-amine, and with the further proviso that the composition is substantially free of compounds containing phosphorus.
 10. The lubricant of claim 9, wherein the triazole compound is a 1,2,4-triazole compound.
 11. The lubricant of claim 10, wherein the 1,2,4-triazole compound is a compound of formula I:

where R¹, R² and R³ are independently chosen from a hydrogen atom and a hydrocarbyl group having at least 3 carbon atoms.
 12. The lubricant of claim 11, wherein R¹ is a linear,or branched hydrocarbyl group, and where R² and R³ are hydrogen atoms.
 13. The lubricant of claim 9, wherein the triazole compound is a compound of the formula II,

where R′ and R″ are independently chosen from hydrogen and a C₂ to C₅₀ linear or branched alkyl group, with the proviso that at least one of R′ and R″ is not hydrogen.
 14. The lubricant of claim 13, wherein R′ and R″ are independently chosen from C₄ to C₁₂ linear or branched alkyl groups.
 15. The lubricant of claim 9, wherein the triazole compound is present in an amount ranging from about 0.005 wt. % to about 0.5 wt. %, relative to the total weight of the composition.
 16. The lubricant of claim 9, further comprising at least one additive selected from the group consisting of dispersants, anti-wear agents, antioxidants, friction modifiers, anti-foam agents, pour point depressants and viscosity index improvers.
 17. A method of improving lead corrosion protection of a lubricant composition, the method comprising: providing to a machine a lubricant composition comprising a major amount of a base oil; and a minor amount of a triazole compound, with the proviso that the triazole compound is not an alkyl bis-3-amino-1,2,4-triazole or an oleyl-1,2,4-triazole-3-amine, and with the further proviso that the composition is substantially free of compounds containing phosphorus, wherein the lubricant composition provides improved lead corrosion protection as compared to the same composition that is devoid of the triazole compound, where both compositions are employed under the same machine operating conditions over the same period of time.
 18. The method of claim 17, wherein the triazole compound is a 1,2,4-triazole compound.
 19. The method of claim 17, wherein the machine is selected from the group consisting of spark ignition and compression-ignition internal combustion engines.
 20. The method of claim 19, wherein the engine is selected from the group consisting of diesel engines, marine engines, rotary engines, turbine engines, locomotive engines, propulsion engines, aviation piston engines, stationary power generation engines, continuous power generation engines, engines comprising silver parts, and engines comprising lead parts.
 21. The method of claim 17, wherein the machine is a medium speed diesel engine.
 22. A method for operating a machine comprising: providing to a machine a lubricant composition comprising a major amount of a base oil; and a minor amount of a triazole compound, with the proviso that the triazole compound is not an alkyl bis-3-amino-1,2,4-triazole or an oleyl-1,2,4-triazole-3-amine, and with the further proviso that the composition is substantially free of compounds containing phosphorus.
 23. The method of claim 22, wherein the machine is selected from the group consisting of spark ignition and compression-ignition internal combustion engines.
 24. The method of claim 23, wherein the engine is selected from the group consisting of diesel engines, marine engines, rotary engines, turbine engines, locomotive engines, propulsion engines, aviation piston engines, stationary power generation engines, continuous power generation engines, engines comprising silver parts, and engines comprising lead parts.
 25. The method of claim 22, wherein the machine is a medium speed diesel engine.
 26. A method of lubricating at least one moving part of a machine, said method comprising: contacting the at least one moving part with a lubricant composition comprising a major amount of a base oil; and a minor amount of a triazole compound, with the proviso that the triazole compound is not an alkyl bis-3-amino-1,2,4-triazole or an oleyl-1,2,4-triazole-3-amine, and with the further proviso that the composition is substantially free of compounds containing phosphorus.
 27. The method of claim 26, wherein the machine is selected from the group consisting of spark ignition and compression-ignition internal combustion engines.
 28. The method of claim 27, wherein the engine is selected from the group consisting of diesel engines, marine engines, rotary engines, turbine engines, locomotive engines, propulsion engines, aviation piston engines, stationary power generation engines, continuous power generation engines, engines comprising silver parts, and engines comprising lead parts.
 29. The method of claim 26, wherein the machine is a medium speed diesel engine.
 30. An additive package composition comprising: a diluent; and a triazole compound of the formula II,

where R′ and R″ are independently chosen from hydrogen and a C₂ to C₅₀ linear or branched alkyl group, with the proviso that at least one of R′ and R″ is not hydrogen.
 31. The additive package composition of claim 30, wherein the additive package is essentially free of zinc dialkyldithiophosphates.
 32. The additive package composition of claim 30, wherein the triazole compound is present in an amount ranging from about 0.1 wt % to about 5 wt % relative to the total weight of the additive package composition.
 33. The additive package composition of claim 30, further comprising one or more additional additives chosen from dispersants, detergents, anti-wear agents, supplemental antioxidants, viscosity index improvers, pour point depressants, corrosion inhibitors, rust inhibitors, foam inhibitors, anti-swell agents and friction modifiers.
 34. The additive package composition of claim 30, wherein R′ and R″ are independently chosen from C₄ to C₁₂ linear or branched alkyl groups.
 35. A lubricant composition comprising: a major amount of a base oil; and a minor amount of a triazole compound of the formula II,

where R′ and R″ are independently chosen from hydrogen and a C₂ to C₅₀ linear or branched alkyl group, with the proviso that at least one of R′ and R″ is not hydrogen.
 36. The lubricant of claim 35, wherein the lubricant is essentially free of zinc dialkyldithiophosphate.
 37. The lubricant of claim 35, wherein R′ and R″ are independently chosen from C₄ to C₁₂ linear or branched alkyl groups.
 38. The lubricant of claim 35, wherein the triazole compound is present in an amount ranging from about 0.005 wt. % to about 0.5 wt. %, relative to the total weight of the composition.
 39. The lubricant of claim 35, further comprising at least one additive selected from the group consisting of dispersants, anti-wear agents, antioxidants, friction modifiers, anti-foam agents, pour point depressants and viscosity index improvers. 